DIY epoxy blacking.

[rusty69]

 

This year, me and the good Mrs Rust are going to attempt to epoxy the previously bitumened sides (not the base) of our 70ft narrowboat. We are booked out for two weeks, but as the time draws nearer, I am beginning to worry that we may be biting off more than we can chew. For reference we have in the past always used bitumen, and have successfully managed to do sides and baseplate within a week between us.

I have looked into various coatings , and have discounted the chemco glass flake epoxy, and the Sherwin Williams epoxy on cost grounds.

I am currently still considering the Jotun Jotmastic 90 or the SML paints Ballastic epoxy.
I have discovered that a Tercoo rotating blaster is a good option for bitumen removal, but the triple disc offering, though effective, is still a very slow process.

So, what is the best method to attack this:

1. Prep the whole surface to be coated in one hit and then apply epoxy by brush or roller?

2. Prep a bit at a time, say 20ft and then epoxy and repeat.

3. Bribe family members to come and lend a hand

4. Forget about the epoxy and just stick some more bitumen on.

Any advice on how to approach it, equipment required, techniques gratefully received.

[Alan de Enfield]

15 minutes ago, rusty69 said:

So, what is the best method to attack this:

 

 

Find "a man who can"

Get deck chair out

Sit in deck chair

Get beer out and drink

Watch man work

Get wallet out

Pay man

Go cruising

[Jon57]

3 minutes ago, rusty69 said:

 

This year, me and the good Mrs Rust are going to attempt to epoxy the previously bitumened sides (not the base) of our 70ft narrowboat. We are booked out for two weeks, but as the time draws nearer, I am beginning to worry that we may be biting off more than we can chew. For reference we have in the past always used bitumen, and have successfully managed to do sides and baseplate within a week between us.

I have looked into various coatings , and have discounted the chemco glass flake epoxy, and the Sherwin Williams epoxy on cost grounds.

I am currently still considering the Jotun Jotmastic 90 or the SML paints Ballastic epoxy.
I have discovered that a Tercoo rotating blaster is a good option for bitumen removal, but the triple disc offering, though effective, is still a very slow process.

So, what is the best method to attack this:

1. Prep the whole surface to be coated in one hit and then apply epoxy by brush or roller?

2. Prep a bit at a time, say 20ft and then epoxy and repeat.

3. Bribe family members to come and lend a hand

4. Forget about the epoxy and just stick some more bitumen on.

Any advice on how to approach it, equipment required, techniques gratefully received.

I’ve used the Tercoo triple on my hull. It’s a good bit of kit for getting down to bare steel, but slow progress and dusty. Doesn’t like false rivets or tight edges as it can damage the tungsten teeth so save them till last, or use a single Tercoo.  Two would possibly do a 70ft Narrowboat sides only. I used the SML ballistic black epoxy that goes over existing blacking. I’m doing the baseplate on mine in May so will Know how it’s performed. Did mine (56ft) in a week with help but it was hard work.

[rusty69]

6 minutes ago, Jon57 said:

I’ve used the Tercoo triple on my hull. It’s a good bit of kit for getting down to bare steel, but slow progress and dusty. Doesn’t like false rivets or tight edges as it can damage the tungsten teeth so save them till last, or use a single Tercoo.  Two would possibly do a 70ft Narrowboat sides only. I used the SML ballistic black epoxy that goes over existing blacking. I’m doing the baseplate on mine in May so will Know how it’s performed. Did mine (56ft) in a week with help but it was hard work.

Thanks Jon.

 

As you have experience of the Tercoo can you estimate how many man (and woman) hours it might take to do both sides of a 70ft (Maybe 50 square metres).

 

It will be interesting to see how your ballastic (ballistic) has fared. How did you prep the hull to take it?

Edited January 27, 2023 by rusty69

[Mike Adams]

Unless you can get all the bitumen off, and this can only be done by blasting, then I would just use a single pack bitumen type paint. You cannot get the surface clean enough by any other method and you are very temperature and weather dependant. A few coats of bitumen after pressure washing will last 2 or 3 years and save up your money for a decent professional blast and epoxy in controlled conditions and a lot of physical grief.

[rusty69]

4 minutes ago, Mike Adams said:

Unless you can get all the bitumen off, and this can only be done by blasting, then I would just use a single pack bitumen type paint. You cannot get the surface clean enough by any other method and you are very temperature and weather dependant. A few coats of bitumen after pressure washing will last 2 or 3 years and save up your money for a decent professional blast and epoxy in controlled conditions and a lot of physical grief.

Thanks Mike. That is one of the questions I was trying to get answered, whether DIY ing it can get the surface to a good enough finish to either take Jotun 90 or the Ballastic stuff. Clearly grit blasting is the ultimate solution, but others seem to have gone the DIY route.

 

If the answer is no, then as you say, we may as well go the bitumen route. 

[David Mack]

The preparation and the weather will be the time-critical issues. Two of you with 4" foam rollers can paint epoxy over a 70ft hull side in a couple of hours. With care you can do it all with the roller, even the awkward nooks and crannies, and you don't need a brush. Don't bother with roller trays - just dip the roller in the paint can.

At the end of the day throw away the roller sleeves.

Toolstation do solvent-resistant roller sleeves for use with epoxy. Ordinary rollers may dissolved in the solvent leaving you with fluff on the hull.

https://www.toolstation.com/rota-solvent-resistant-roller-sleeves/p45894

 

[ditchcrawler]

5 minutes ago, rusty69 said:

Thanks Mike. That is one of the questions I was trying to get answered, whether DIY ing it can get the surface to a good enough finish to either take Jotun 90 or the Ballastic stuff. Clearly grit blasting is the ultimate solution, but others seem to have gone the DIY route.

 

If the answer is no, then as you say, we may as well go the bitumen route. 

I am in the dry dock for reblacking this  May, I had it done with 2Pk over bitumen 4 years ago following high pressure power wash. The decision on whether to go 2pk again or straight bitumen I will make after its been washed off. From what I can see with it afloat it will be 2pk again but I wont know until May.

[David Mack]

And if you are pushed for time do all the hull from the bottom up to 6" above the water line first and get that painted. The rest can be done with the boat afloat if you time out on dock

[Jon57]

3 minutes ago, rusty69 said:

Thanks Jon.

 

As you have experience of Tercoo can you estimate how many man (and woman) hours it might take to do both sides of a 70ft (Maybe 50 square metres).

 

It will be interesting to see how your ballastic (ballistic) has fared. How did you prep the hull to take it?

I only went back to bare metal on the rubbing stake up to the gunnels, and a few places below, the rest I wired cupped the hull that took 8 man days. The application of the epoxy is easy but you only have to mix what you can put on in the time frame. Try and break up the work so you could do it in sections prep paint to have a idea of how it going. What epoxy you use will dictate how much prep you need to do. Obviously full shot blasting is the best way to go but I’m going to see how the Ballistic black epoxy which goes over existing blacking performs. The cost over ordinary blacking products and prep isn’t a ball breaker. 

[Tacet]

Bitumen jumps off if you so much as show it a smear of diesel.  Failing this, rub it with an ice cube, to replicate a boat passing when there is a bit of frost on the canal.

[rusty69]

8 minutes ago, ditchcrawler said:

I am in the dry dock for reblacking this  May, I had it done with 2Pk over bitumen 4 years ago following high pressure power wash. The decision on whether to go 2pk again or straight bitumen I will make after its been washed off. From what I can see with it afloat it will be 2pk again but I wont know until May.

Thanks. I am out after that, so it looks like I will be asking you and Jon in May for your results.

 

Out of interest, what epoxy did you go for?

13 minutes ago, David Mack said:

The preparation and the weather will be the time-critical issues. Two of you with 4" foam rollers can paint epoxy over a 70ft hull side in a couple of hours. With care you can do it all with the roller, even the awkward nooks and crannies, and you don't need a brush. Don't bother with roller trays - just dip the roller in the paint can.

At the end of the day throw away the roller sleeves.

Toolstation do solvent-resistant roller sleeves for use with epoxy. Ordinary rollers may dissolved in the solvent leaving you with fluff on the hull.

https://www.toolstation.com/rota-solvent-resistant-roller-sleeves/p45894

 

Thanks for the heads up on the roller sleeves. I reckon painting it will be the easy bit, its the prep that's gonna kill us.

[Jon57]

2 minutes ago, rusty69 said:

Thanks. I am out after that, so it looks like I will be asking you and Jon in May for your results.

 

Out of interest, what epoxy did you go for?

Thanks for the heads up on the roller sleeves. I reckon painting it will be the easy bit, its the prep that's gonna kill us.

Yep 😩😩

[rusty69]

10 minutes ago, Jon57 said:

I only went back to bare metal on the rubbing stake up to the gunnels, and a few places below, the rest I wired cupped the hull that took 8 man days. The application of the epoxy is easy but you only have to mix what you can put on in the time frame. Try and break up the work so you could do it in sections prep paint to have a idea of how it going. What epoxy you use will dictate how much prep you need to do. Obviously full shot blasting is the best way to go but I’m going to see how the Ballistic black epoxy which goes over existing blacking performs. The cost over ordinary blacking products and prep isn’t a ball breaker. 

Wow, 8 days. Were gonna need a smaller boat. What size boat you got?

[Jon57]

Just now, rusty69 said:

Wow, 8 days. Were gonna need a smaller boat. What size boat you got?

That’s for the prep of a 56ft sides only. 

[rusty69]

16 minutes ago, David Mack said:

And if you are pushed for time do all the hull from the bottom up to 6" above the water line first and get that painted. The rest can be done with the boat afloat if you time out on dock

Good idea. I had thought about doing this, perhaps using a hot air gun and a scraper to attack the soft bitumen. I'm not even convinced the bit above the waterline is worth epoxying tbh.

1 minute ago, Jon57 said:

That’s for the prep of a 56ft sides only. 

I suppose your days weren't 4 hours long by any chance?

[ditchcrawler]

16 minutes ago, rusty69 said:

Thanks. I am out after that, so it looks like I will be asking you and Jon in May for your results.

 

Out of interest, what epoxy did you go for?

 

It was done at Northwich Dry Dock, they do the boats from Ellesmere Museum with the same system.

Hull Blacking Service | The Northwich Drydock Company

Edited January 27, 2023 by ditchcrawler

[Jon57]

1 minute ago, rusty69 said:

Good idea. I had thought about doing this, perhaps using a hot air gun and a scraper to attack the soft bitumen. I'm not even convinced the bit above the waterline is worth epoxying tbh.

If the bitumen is stuck like the proverbial shit to a blanket it’s ok to leave as is. Only the loose bits need to removed. The SML is (Supposed) to seal and stick to it if just wired cupped. Will find out soon. 

[matty40s]

I've used the Dacrylate Epidac 2 pack the last time OF has been out in 2019, I'm hoping for a slot in September to see how its going.

[rusty69]

10 minutes ago, matty40s said:

I've used the Dacrylate Epidac 2 pack the last time OF has been out in 2019, I'm hoping for a slot in September to see how its going.

Thanks. Not heard of that one, will have a look.

What prep did you do?

Edited January 27, 2023 by rusty69

[PaulJ]

If you are going to use a Tercoo I would (and did) get the 7 disc jobbie and a cheap polisher off Ebay- I got a Silverline 1200watt which runs at a sensible speed and is fairly comfy to hold.

Still fairly slow going and you have to be gentle with them. Just stroke the hull and it will do a good job and you will have some tips left. 

As Jon57 says- they dont like anything that sticks out much.

[rusty69]

1 minute ago, PaulJ said:

If you are going to use a Tercoo I would (and did) get the 7 disc jobbie and a cheap polisher off Ebay- I got a Silverline 1200watt which runs at a sensible speed and is fairly comfy to hold.

Still fairly slow going and you have to be gentle with them. Just stroke the hull and it will do a good job and you will have some tips left. 

As Jon57 says- they dont like anything that sticks out much.

Thanks. What is the polisher for? I was under the impression the Tercoo thing fits in a drill. 

 

Is it likely to loose teeth on contact with the rubbing bands? 

[Jon57]

2 minutes ago, rusty69 said:

Thanks. What is the polisher for? I was under the impression the Tercoo thing fits in a drill. 

 

Is it likely to loose teeth on contact with the rubbing bands? 

You can get Tercoo discs up to seven I believe. They do a special machine for them. You will need arms like popeye.😬

[rusty69]

Just now, Jon57 said:

You can get Tercoo discs up to seven I believe. They do a special machine for them. You will need arms like popeye.😬

Yeah. I've seen the video on YouTube. I did look for somewhere that might hire one, but no luck so far. 

 

Got lots of spinach though (for Mrs R) 

[Jon57]

4 minutes ago, rusty69 said:

Yeah. I've seen the video on YouTube. I did look for somewhere that might hire one, but no luck so far. 

 

Got lots of spinach though (for Mrs R) 

The 3 disc is ok in a cheap drill, nice and light. Pack it off with some wood blocks and gaffer tape so the disc is just the right distance then you just have to keep going up and down (10000000000 times🤣)